(setq python-shell-interpreter "python"
      python-shell-interpreter-args "-i /absolute/path/to/manage.py shell_plus")

(defun start-my-ipython-term ()
  (interactive)
  (ansi-term "/usr/bin/ipython"))
(global-set-key (kbd "<your keybinding here>") 'start-my-ipython-term)

#!/bin/sh
set -e

/bin/echo -n "Select Django project/dir, or press enter for plain ipython: "

read selection
case $selection in
    '') exec ipython ;;
    project) cd /Users/japhy/Projekty/some/project/dir ;;
    # other often used projects go here
    *) cd $selection ;;
esac
exec python manage.py shell

#!/bin/sh
set -e

/bin/echo -n "Select Django project/dir, or press enter for plain ipython: "

read selection
case $selection in
    '') exec ipython ;;
    project) cd /Users/japhy/Projekty/some/project/dir ;;
    # other often used projects go here
    *) cd $selection ;;
esac
exec python manage.py shell

((python-mode
  (python-shell-interpreter . "python")
  (python-shell-interpreter-args . "/home/youruser/code/yourproject/manage.py shell")
  (python-shell-prompt-regexp . "In \[[0-9]+\]: ")
  (python-shell-prompt-output-regexp . "Out\[[0-9]+\]: ")
  (python-shell-completion-setup-code . "from IPython.core.completerlib import module_completion")
  (python-shell-completion-module-string-code . "';'.join(module_completion('''%s'''))n")
  (python-shell-completion-string-code . "';'.join(get_ipython().Completer.all_completions('''%s'''))n")
  (python-shell-extra-pythonpaths "/home/youruser/code/yourproject/apps/")
  (python-shell-virtualenv-path . "/home/youruser/.virtualenvs/yourproject")))

M-x shell

prompt> cd path/to/my/django/directory
prompt> python manage.py shell
Python 2.6.1 (r261:67515, Jul  7 2009, 23:51:51)
[GCC 4.2.1 (Apple Inc. build 5646)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
(InteractiveConsole)
>>>